Electric fuse holder



May 12, 1953 c. J. WARD ELECTRIC FUSE HOLDER Filed Dec. 24, 1949 5INVENTOR. cunRLEs .s. WARD ATTORNEY Patented May 12, 1953 FUSE; HOLDER-Charles: I. Wand; Philadelphia, Pa., assignoc to Hugh- Ri By; 1 10,,Philadelphia, Eat, a compo; rafion-oflrennssrljvsniaApnlicotionneccmhcr. 24, 13.49,.Serial1Nc. 134,927

This invention relates to fuses and more Q3.1"- ticular to animprovement in fuse holders and; proteotots, which are adapted; for, usein mounting cartridge type fuses for the protection of automobile,lighting, generator-andbattery circuits" or' for use in the wiring ofother electrical and electronic equipinei t.

One of the principal objects of the. intention is to provide a fuseholder capable of use in an individual wire of circuit and which willbe. supported by the wiring, avoiding the necessity for a central fusepanel to whicl'i extra leng tlis of must be run. The improved fuseholder. may be supplied in assembled form. inducing;

fuse, connector elements, and conductor Wires, so that a completesection of wiring, with e. protected. fuse thetein,.msy be. provided,fol: re-

.it purposes. Altemativcly the fuse. holds component. parts, less. the.conducts: my supplied for use xvii h existing. wir- In such case theexisting ring may be.

s e in nature, may then. be assembled o e. the and secured togetloervwith. its contsin iuse electrics-11;? connected to the ends ol the. outWire.

Another. major object of the invention lies. in provision of a.multipeirt fuse holder capable. of entirely enclosing a fuse andprotecting it from physical injury, access of. (ii-it. gtease .i' oil,and which is further capable-oil insulating said fuse from sli Itciiicuiting Contact with adjacent metal objects.

Another object of the. invention lies. in the provision of a. multipart.fuse holder Whose. parts are so 0 .istructed as to, be easily andquickly separable for th replacement of. a. blown. fuse, and ch. is.further capable of being quickly reass sled. without need for specialtools or .suzning. manual operations.

Still, ll-31' object of the invention is. to pro.-

a. muitipaizt holder... for encasi-ng a cartridge type in which willmaintain the teliminal caps of the in good. electrical contact, underpress sure, with the eon-nector'elements. of, a; sir cuit the somepressure means, within the holder, being also utilized to maintain the.parts of the hold r closed and locked condition- A 1]; further purposeof the invention resides in the provision of a fuse holder and protectorof loch-ably secured casing parts which are. of relatively inexpensivemolded construction and whose internally assembled metal parts are alsoinexpensively fabricated by metal stamping and vide forming--operations, avoiding the necessity fOl" costlymocl'i-ining operations.

These and still other objects of the invention Will become more apparentfromai'cading: of the description of one embodiment of the inventionwhich has been selected for illustrative purposesand which is showninthe attached drawings.

Referringto the drawings:

Figure l is a plan view ofalength of Wiring capable of use as a. circuitsection, including a fuse, and the fuse holder assembly with its parts.shown in their separated relationship on the Wiringas if ready forreplacement of the fuse.

Figure 2 is an enlarged plan view of the fuse holder with its casingparts in joined relationship, occupying theii normel' positions as afterinsertion of a fuse, and ready for use in the circuit.

Figure 3 is longitudinal sectional viewof the fuse holder token axiallythereof on line 3 of Figure. 2 show-mg the other elements or the fuseholder assembly, inolumg a. fuse, inelevation therein.

Figure 4 is a sectional ti of Figure 5, and is simall" to that shownFigure 3 but with the 3 parts. ed complctc- 13 together in the mannerrequired price todis assemlolg of" the holders.

Figure 5 is an elevationel view showing part of the fuse holder with thecasing members pusl'ied' completely together as in Figure 4.

Figure 6- ison elevationel' View to Fig:- ure 5 but with the casingparts rotated relative to each other in the ni-anne 'requi'zed forsepamtionand clisassemb-ly;

Figure "1 is a, sectional view perpendicular to the axis of'the fuseholder taken on line l-l' Figure Figure 8 is a sectional view s ilor tothat of Figure 7' taken line i -ll of k 6 with the casing parts'rotetecli disassembl'.

Figure 9 is an end view of one of the casing partsof the taken along-9-4) of Figure I.

Figure 10 is an entli view of the other of said casing parts taken aline iil lll oi? Figure 1.

Figure 11 is on end v1 of saitl last mam-eel cos-- ing part taken alonge i i-H of Figure l.

v Figure 12 is a, sectional View taken along line Figure 13 is asectional view taken alon line l-3l3 of Figure l, and showing one of thepro- .ieotions wl'iichv is an element of bayonet type securing means forthe parts.

The. specific embodiment of the invention selected for illustration inthe drawings is adapted to hold a fuse H) of the conventional cartridgepart of the side wall of which is preferably split,

lengthwise, as at 2!, to enable the fuse cap to spread the side wall ofthe connector element upon insertion, thus causing the fuse cap to beresiliently grasped under pressure by said split wall of the cup-shapedpart of the connector element. A plurality of lugs 22, see Figures 3 and4,

are bent inwardly from the side wall of each connector element, to formthe base of the cup. each element including also an end lug 23 which isbent inwardly as at 24 and thence at right angles axially of the cup.The outer extremities of each end lug 23 are adapted to be crimped overa conductor wire end for securement and electrical connection thereto.The illustrated wires of the circuit are referenced 25 in the drawings,and are preferably provided with ring terminals 26 at their outer ends.

A helical coil spring 30 is floatingly carried around one of theconductor wires 25, this spring being preferably formed with flattenedend turns to provide planar ends. One end of the coil spring is adaptedto abut the base 22 of one of the above described connector elements,while the other end of the coil is adapted to abut an internal shoulderin the fuse holder as will be shortly described.

The fuse holder includes two casing members and 50 which are detachablysecured together to completely enclose and protect the fuse it. Thecasing members are preferably molded of suitable insulating material andare preferably tubular in shape. Member 40 is provided with an internalbore 4! slightly larger than the diameter of the connector element 2 I,the member 50 being also provided with a bore 5| of equal diameter. Whenthe casing members are secured together with their respective bores inaxial a1inement, said members protectively enclose the fuse, theconnector elements and the spring described above. The bore 4|communicates with the exterior of casing member 40 through an opening 42of reduced diameter suitable for passage of wire 25, while a similarreduced passage 52 is provided at the opposite end of easing member 50.The presence of the reduced opening 42 provides a beveled shoulder 43 atthe outer end of bore 4!. The base lugs 22 and the inturned part 24 oflug 23 of one of the connector elements abuts this shoulder 43 when thefuse holder is assembled. In like manner a square shoulder 53 isprovided at the outer end of bore 5i to provide a seat for the outer endof the coil spring 30.

Casing member 40 is provided with a cylindrical surface 44 which isadapted to be telescopically received within an enlarged mouth 54 formedin the end of the bore 5! of the casing member 50. A pair ofdiametrically opposed bayonet lugs 45-45 project outwardly from thesurface 44 of the member 40, while a pair of diametrically opposedgrooves 55-55 are formed in the mouth 54 of easing member for axialsliding reception of the lugs 45-45, respectively. In addition, a pairof circumferential slots 56 are provided, which respectively communicatewith the grooves -55 to form therewith internal bayonet type slots foraccommodation of the bayonet lugs 45-45. Each of these slots extendsoutwardly and is open to the outer surface of the casing member 50 asshown in Fig ure 2, rendering the positions and operational movements oflugs 45 visible from the exterior of the fuse holder. Each of the slots55-55 is provided with an end notch 51 providing a detaining seat forthe lug 45 when the latter is in its final inserted position within itsaccommodating bayonet groove.

Casing member 40 is provided with a portion of enlarged diameter havinga grooved or ridged peripheral surface 41 to facilitate finger graspingand prevent slippage. A flattened surface 58, best shown in Figures 2and 11, facilitates manual gripping of easing member. The two casingmembers are adapted to be brought together, when grasped on the surfacesmentioned, and portion 44 of one member telescoped into the widenedmouth 54 of the other, with the lugs 45 entering slots 55 in the face ofthe second member. If the casing members 40 and 50 are then pushedtogether until the end faces 45 and 59 thereof meet they may berelatively rotated for approximately 50 with the lugs 55 traveling inslots 56 until the lugs are in alignment with their detaining notches51. At this time, release of the casing members causes the lugs 45 toenter the slots 51 under pressure of the compressed coil spring 39. Thebayonet lug 45 is then seated in its detaining notch 5'! as shown inFigure 2 and rotational disengagement of the bayonet type connection isprevented by pressure of the compressed coil spring 35. When thus lockedagainst rotation, the end faces 59 and 59 are slightly separated as arethe complementary bevel surfaces BI and 52 provided on the casingmembers 40 and 50 respectively. The presence of these bevels maintainsthe internal chamber closed against direct entry of foreign objects eventhough spread slightly.

When it is desired to separate the casing members of the fuse holder inorder to inspect the fuse or replace a blown fuse, the two casingmembers 40 and 58 are again grasped and pushed together to occupy theirpositions of Figure 5. This movement releases the lug from its detainingnotch 57 and permits relative rotational movement of the casing parts.When the lug 45 comes into alignment with the slots 55, pressure of thecoil spring will force the two casing members apart and completelyseparate them, the lug traveling along groove 55. It is then onlynecessary to pull apart the two expose-d con nector elements 20 todisengage the blown fuse. A new fuse is then inserted between theconnector elements, and the casing members may then be pushed togetherto surround the fuse and secured in locked relationship in the mannerpreviously described.

It will be noted that the coil spring 35 is compressed between one ofthe connector elements 20 and the internal shoulder 53 when the pair ofcasing members are secured and locked together as shown in Figure 3, thefuse being prevented from movement to the left by abutment of the otherconnector element against shoulder 43.

Compression of the coil spring holds the fuse firmly in place withlowered contact resistance, and at the same time exerts a separatingforce on the two casing members. It is this force which maintains thesemembers locked against relative rotation for disassembly throughengagement of lug 45 with the notch 51. Thus, accidental separation ofthe casing members by shaking, jarring or like movements of theapparatus in which the fuse holder may be mounted is effectuallyprevented. In order to accomplish their separation it is necessary towilfully press the two casing members together for release of theirlocking engagement.

It will be obvious to one skilled in the electrical arts that manymodifications may be made in the shape, size, configuration and materialof the fuse holder of this invention without departing from itsteachings and spirit. The holder and protector may be utilized not onlyin the types of circuits enumerated above but in any wiring where itwould be desirable to fuse individual circuits without lengthening andextending the wires to a central fuse panel. For example, such otherapplication may well be made in the wiring of telephone, telegraph,radio and television apparatus. The holder may be modified toaccommodate a plurality of fuses and thus adapted to the fusing ofmultiple circuits. It is, therefore, desired that the invention not berestricted to the specific construction shown in the drawings but belimited only by the scope and spirit of the appended claim.

What is claimed as new and useful is:

In a fuse holder, a pair of separable members of insulating materialconjointly adapted to form a protective casing for a cartridge fusehaving end terminal caps, each of said members having extending axiallytherethrough an elongated bore terminating at its outer end in a hole ofa diameter less than that of said bore to provide an internal shoulderat the outer end of each member, cup-shaped contact elementsrespectively seated in said bores and respectively embracingly receivingsaid end terminal caps for frictional engagement therewith over a widearea, each of said elements having secured thereto a conductor extendingoutwardly from each of said casing members through the reduced diameterend hole thereof, a coil spring floatingly embracing one of saidconductors and disposed in intervening relation between the contactelement of said conductor and the internal shoulder of the memberaccommodating said last-mentioned contact element, said casing membersbeing respectively provided at their inner connecting ends withinterfitting male and female portions adapted to be interconnected andlocked together by coacting bayonet and slot means which include anexternal projection on the male portion of one member and an internalgroove on the female portion of the other member, the arrangement beingsuch that upon interlocking assembly of the casing members with thecartridge fuse enclosed thereby the said coil spring exerts its pressureaxially against the cartridge fuse to secure the latter between saidcup-shaped contact elements and to maintain said casing members lockedtogether.

CHARLES J. WARD.

References Cited in the file of this patent UNITED STATES PATENTS NumberName Date 1,601,673 Bridgman Sept. 28, 1926 1,602,227 Hentschel Oct. 5,1926 1,798,860 Woodruff Mar. 31, 1931 1,969,301 Edwards Aug. 7, 19342,288,680 Chandler July 7, 1942 FOREIGN PATENTS Number Country Date335,642 Great Britain Oct. 9, 1930

